This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The minichromosome maintenance (MCM) complex is an ATP-dependend DNA helicase essential for DNA replication in eukaryotic cells, but it's function is poorly understood. In particular, it is unknown how the specific subunits of the MCM complex interact at various stages of DNA binding and unwinding. We intend to use SAXS to understand the overall assembly and subunit interactions of the MCM complex in the context of ATP and DNA binding.